LAUSR

BACKGROUND To clarify that intercropping and nitrogen application changed the microclimate of faba bean canopy and further affected the yield, the relationship between microclimate of intercropping faba bean canopy and yield and its response to nitrogen application were studied in crop canopy. RESULTS In the field experiments in Eshan and Xundian, The growth index, light transmittance, interception rate of photosynthetic effective radiation, temperature, relative humidity and yield of faba bean were determined by using three planting methods (wheat monoculture, faba bean monoculture and wheat/faba bean intercropping) and four nitrogen application levels (N0(0kg/ha), N1(45kg/ha), N2(90kg/ha) and N3(180kg/ha)). The results showed that nitrogen application significantly improved the growth index of monoculture and intercropping broad beans, significantly reduced the canopy light transmittance and temperature, and significantly increased the interception rate and relative humidity of photosynthetic effective radiation. Compared with N0, the yield of broad bean in both places was the highest in N1, which increased by 14% and 15% respectively. CONCLUSION Multiple linear stepwise regression and path analysis showed that the decrease of canopy light transmittance during pod setting stage and the interception rate of photosynthetic effective radiation during pod bulging stage of faba bean caused by excessive nitrogen application were the main climatic and ecological factors limiting the increase of intercropping faba bean yield in Eshan and Xundian respectively. The optimum nitrogen application rate recommended in production is 45 kg/hm2 , to reduce the nitrogen application rate and maximize the productivity of wheat and faba bean system. This article is protected by copyright. All rights reserved.